Mun orbit rendezvous help

[Shea25]

Hey, I am having troubles trying to dock with my return vessel left in muns orbit, any tips would be very appreciated. 

Currently I am leaving the return vessel in a 20k high orbit, I land on mun with my small lander and have enough fuel to get back. The problem is I can't for the life of me figure out when or how to launch to meet back up with my return vessel 

 

Thanks 

[diomedea]

If your lander is on the equator and the return vessel has a 0° inclination, then you should simply launch (east, unless that return vessel is in a retrograde orbit therefore west) a bit before the return vessel overflies the landing position, and climb to its orbital altitude keeping the same 0° inclination. But if you're not, we have to wait for the orbit of the return vessel to be close to overfly the landing position and launch at the same inclination it has (because Mun rotates, slowly, it may take time for the orbit to move in relation to the landing position so to align).

Once on an orbit coplanar with the return vessel, you can use normal rendez-vous procedure (hope you already practiced that, if not do with the training scenario before).

[bewing]

A test launch is often useful to help with launch timing. As diomedea said, hopefully everything is equatorial here -- otherwise it gets more complicated. But just do a quicksave, and then wait until your return vessel is exactly overhead. Then launch and circularize, and then see how far ahead of you the return vessel got while you were ascending. Then subtract in your head, reload the quicksave, and launch that much before the return vessel flies over your head. One thing that can help, is that when you are most of the way to orbit, you can turn on targeting mode and consider the whole last half of your ascent to be a high-speed docking maneuver. As diomedea said, hopefully you have practiced a fair bit on the details of finalizing a docking, and basic docking maneuvers.

 

[Kryxal]

If you don't feel like doing all that, just launch a bit late and go for an orbit at 10 km, then plan a transfer to intercept the ship.  As long as you launch into the same plane, it's not really tricky, just set up a maneuver to reach the other orbit and slide it along or add orbits to execution time.

[DD_bwest]

what i do to launch to the right inclination is to launch with the orbit marker directly above and the command  vessel ahead of your position, boost up briefly  then aim directly at the target with sas for a sec, this will put your prograde practically  in the same inclination, then just follow that intol orbit.  put yourself in a 30km or a 40km orbit and match inclinations at the nearest an/dn to put it spot on.   now follow normal rendezvous steps to wait until its coming up behind, create a node to lower your pe to intercept, and slide its timing until you get a good one.

 

unless your playing to max realism and dont want your kerbals waiting around orbit for a while, exact positioning isnt all that important, just matching inclination. 

Edited January 13, 2017 by DD_bwest